回答
2021-03-02 11:22:44
Kevin@MusicoLingo
その部屋に「加えられている」とか、「付いている」というようなニュアンスです。主語が非生物で、動詞が have のときに、このような形になることがよくあります。to it の前に動詞の過去分詞があると考えれば、お分かりかと思います。
This place has a mysterious atmosphere (added) to it.
This place has a mysterious atmosphere (attached) to it.
This box has a frog in it.
This box has a frog (hidden) in it.
This book has important information in it.
This book has important information (described) in it.